import React, { Component } from 'react'

export default class Demo extends Component {
    state = { count: 0 }

    add = () => {

        //对象式的setState
        // //1.获取原来的count值
        // const { count } = this.state;

        // //2.更新状态
        // this.setState({ count: count + 1 }, () => {
        //     console.log('12行的输出', this.state.count)
        // })
        // // console.log('12行的输出', this.state.count)

        //函数式的setState
        this.setState(state => ({ count: state.count + 1 }))

        // this.setState({ count: this.state.count + 1 })
    }

    render() {
        return (
            <div>
                <h1>当前求和为：{this.state.count}</h1>
                <button onClick={this.add}>点我+1</button>
            </div>
        )
    }
}
